# #399bb1

A color — cool, modern. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#399bb1`
- RGB: rgb(57, 155, 177)
- HSL: hsl(191, 51%, 46%)
- OKLCH: oklch(0.642 0.095 215.5)
- Relative luminance: 0.2749
- Nearest named color: Blue Moon (#3992a8, Δ 2.652) — https://brandsweets.com/colors/blue-moon
- Moods: cool, modern
- Page: https://brandsweets.com/colors/399bb1

## Tints & shades

- Tints (toward white): #42aac2, #56b3c8, #6dbdd0, #80c6d6, #93cfdc, #a6d7e2, #bae0e9, #d1eaf0, #e4f3f6, #f7fcfd
- Shades (toward black): #348ea2, #2f8092, #296f7f, #246270, #1f5460, #1a4751, #153941, #0f282e, #0a1b1f, #050d0f

## Harmonies

- Complementary: #b14f39
- Analogous: #39b18b, #395fb1
- Triadic: #b1399b, #9bb139
- Split-complementary: #b1395f, #b18b39
- Tetradic: #8b39b1, #b14f39, #5fb139

## Colors that go with #399bb1

Named partners (harmony on the OKLCH wheel, co-occurrence in curated palettes and brand systems, and the neutrals that carry it), best first:

- **Charcoal** #36454f [role, pool] — Charcoal is the text near-black for #399bb1: softer than #000 and cool enough to feel like part of the same palette. Seen in: Lido (https://brandsweets.com/palettes/vivid#lido), Dusty Blue (https://brandsweets.com/palettes/cool#dusty-blue), Coastal (https://brandsweets.com/palettes/cool#coastal), Tide Pool (https://brandsweets.com/palettes/cool#tide-pool). — https://brandsweets.com/colors/charcoal
- **Orange Red** #ff4500 [harmony, pool: complementary] — Orange Red sits directly opposite #399bb1 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Launch Orange (https://brandsweets.com/palettes/bold#launch-orange), Cursor (https://brandsweets.com/colors/brands/cursor-com), Substack (https://brandsweets.com/colors/brands/substack-com), Figma (https://brandsweets.com/colors/brands/figma). — https://brandsweets.com/colors/orangered
- **Amber** #ffbf00 [pool] — Amber is paired with #399bb1 in 4 real palettes, including Beach Hut and Wired's brand system, as the supporting colour. Seen in: Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Wired (https://brandsweets.com/colors/brands/wired-com), Salesforce (https://brandsweets.com/colors/brands/salesforce-com), Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com). — https://brandsweets.com/colors/amber
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #399bb1: 4 real palettes, including Hershey's's brand system and Fintech Trust, as the supporting colour. Seen in: Hershey's (https://brandsweets.com/colors/brands/hersheys-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Glacier (https://brandsweets.com/palettes/cool#glacier), Blue Mono (https://brandsweets.com/palettes/cool#blue-mono). — https://brandsweets.com/colors/cobalt
- **Copper** #b87333 [pool] — Designers have shipped Copper with #399bb1: 6 real palettes, including Dusk and Clean Beauty, as the accent. Seen in: Dusk (https://brandsweets.com/palettes/cool#dusk), Clean Beauty (https://brandsweets.com/palettes/minimal#clean-beauty), Atelier (https://brandsweets.com/palettes/elegant#atelier), Notion (https://brandsweets.com/colors/brands/notion). — https://brandsweets.com/colors/copper
- **Crimson** #dc143c [pool] — Crimson is paired with #399bb1 in 6 real palettes, including Diner and Retro Pop, as the lead colour. Seen in: Diner (https://brandsweets.com/palettes/vivid#diner), Retro Pop (https://brandsweets.com/palettes/playful#retro-pop), Redfin (https://brandsweets.com/colors/brands/redfin-com), NASCAR (https://brandsweets.com/colors/brands/nascar-com). — https://brandsweets.com/colors/crimson
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #399bb1: 6 real palettes, including Telegram's brand system and Snowflake AI Data Cloud's brand system, as the lead colour. Seen in: Telegram (https://brandsweets.com/colors/brands/telegram-org), Snowflake AI Data Cloud (https://brandsweets.com/colors/brands/snowflake-com), Remix (https://brandsweets.com/colors/brands/remix-run), Astro (https://brandsweets.com/colors/brands/astro-build). — https://brandsweets.com/colors/deepskyblue
- **Denim** #1560bd [pool] — Designers have shipped Denim with #399bb1: 9 real palettes, including Gopro's brand system and Peacock, as the lead colour. Seen in: Gopro (https://brandsweets.com/colors/brands/gopro-com), Peacock (https://brandsweets.com/palettes/vivid#peacock), Dusk (https://brandsweets.com/palettes/cool#dusk), Open House (https://brandsweets.com/palettes/clean#open-house). — https://brandsweets.com/colors/denim

## Contrast (WCAG 2.x, as text)

- On white (#ffffff): 3.23:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #2f8092 (4.54:1); AA: background → #292929 (4.5:1); AAA: text → #235e6c (7.27:1)
- On black (#000000): 6.5:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #3ca2b9 (7.06:1)

## Fonts for this mood

- modern: https://brandsweets.com/fonts/mood/modern

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/399bb1-a2b6be-df4e7a-1f252d-e9f1ef?lock=0&style=vibrant
(Humans lock/regenerate in the tool; the URL is the state — read `lock=` back to see what they kept.)

## Connect an agent

Point any MCP client at the BrandSweets colors endpoint for the same engine:

- Endpoint: https://mcp.brandsweets.com/colors/mcp
- Tools: `analyze_color` (e.g. `analyze_color({ color: "#399bb1" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.